Adjusting mechanism



Feb. 23, 1932.

C. F'. JOHNSON ADJUSTING MECHANISM Filed June 12, 1929 7- lmvsr-v/ar-t 'C/zeszer'fir oiznson. I

=' air metering arrangements Patented Feb. 23, 1932 GHESTER 1F. JOHNSON, OF DETROIT,

PANY Exnouron or slain onns'rnn r. JOHNSON, DECEASED ADJUSTING mEcnAmsm Application filed June 12, 1929. Serial No 370304;. f i i This invention relates broadly to adjusting means embodying both an initial and a limited and continued adjustment, and has spe cial reference to the control of the fuel or for carbureters of internal combustion engines.

It is an object of this invention to provide adjusting means of an improved type having a wide range of initial adjustment together 1 with clamping means therefor which permit a limited subsequent adjustment in either direction from the initial setting, the limited adjustment being designated as a servlce adustment restricted to the desired operating range predetermined by the initial or factory provide an improved adjusting of the air valve.

adjustment which compensates for normal variations in individual structures due to manufacturing tolerances and the like.

It is another object of this invention to means of the type described incorporating two interdependent adjustment ranges.

Qther and further important objects of this invention will be apparent from the disclosures in the specification and accompanying drawings.

The inventlon (111 a preferred form) is illustrated on the drawings and hereinafter more fully described.

On the drawings:

Figure 1 15 a iragmentary showing of a carbureter illustrating the application of a rileviee embodying the features of this inven' tion to the control of a carburetor air valve.

Figure 2 is an enlarged view of the adj usting device, with parts broken away for clearness.

Figure 3 is a fragmentary end view taken from the left of Fig. 2.

As shown on the drawings:

The carbureter features chosen to illustrate an embodiment of this invention comprise an air valve housing 10 within which is an air valve 11 shown in dotted lines, which is pivoted at 12. This valve is normally closed by a spring 13 resting on a movable support 14 which carries a button 15 on its lower end by which the support may be raised to increase the resistance to an opening movement The range of adjustment is madeextreme in order that'the maximum spring pressure so obtainedmay be sufficient to maintain theyvalve seated against the suction within the carbureter when the engine is cranked for starting, thus insuring the de livery of an abnormal amount of fuel due to the increased suction within the carbue reter when the air valve isheldclosed. In efi'ect this forms a primin device analogous tothe elfect of the usual choke valve.

The spring support 14 and button 15 are guided by a housing 16 containing a spring 17 actingagainst the button 15. Associated with the housing is abifurcated yoke 18 forming journals which is bent to formj a handleQO. A lever 911i? clamped by a screw 22 to the shaft 19 and has one end 23 extending througha slot in the housing to engage the button, when the handle 20 is moved counter clockwise, the lever end 23 lifts the button and spring support to increase acting against the air valve. V

In order to limit the return movement of the lever due to the springs 13 and 17,, the lever 21 is formed with an arm 24: adjacent the shank of the yoke 18, and an adjusting screw 25 extends through a threaded aperture in the arm; the end of the screw bearing against the yoke 18. the primary or initial adjustment means for the air valve opening movement and serves to vary the proportioningof fuel to'air by varying the resistance opposing the opening of the air valve.

Y The structure so far described would form for a shaft19 one end of the spring load This screw 25 forms MICHIGAN; nETnoIrAnnsEoum'rY:rnus'r com.

so that an operative combination which in" skilled hands would be satisfactory, but as carbureters are often tinkered with by unskilled operators, itis desirable to limit the range of adjustment tothe most desirable range. To this end a collar 26 is mounted on the screw 25 andis clamped thereto by a set screw lever screw 22,the:free end 29 being. notched i withoutdeparting from. the

' invention,

V screw opposite the clicker member, then the ad usting screw can be shifted 1, 2 or 3' notches-in eitherdirection, a clockwise move.- ment of the screw and collar, for a right hand screw, serving to enrich the mixture, and vice turn movement of said lever, a notched collar mounted on said screw and clicker means for engaging the notchesin said collar for indicating the degree of adjustment of said screw from normal, said clicker means 00- operating with .said collar to limit the range ofadjustment:ofsaid screw.

In testimony whereof I have hereunto subscribed my name at Detroit, Mich., county,

Wayne..:; V. v

CHESTER FL JOHNSON.

versa, the set screw 27 in either'case bring ing up against the clicker member. to limit.

the range of plus or minus adjustment;

Itwill thus be seen that I have provided an improved and :simplified adjusting .mech-. anism incorporating a wide rangeof primary adjustment together with a limited range of secondaryadjustment.v

7 I am aware thatnumerous detailsof-construction may be varied through a wider-ange principles of this and I therefore do not purpose limiting thepatent granted, otherwise than necessitated by the prior art. I

Iclaim: V a

1. Avariable adjusting device. ofthe class described comprising a longitudinally ad justable member, 'means for limiting the range of movement of said member, including'movable clamping means for said member, said'clamping means forming an indicator. of the-position of said adjustable mem? ber within the range'of movement permitted by said limitingmeans.

2. Air adjusting 'mechanism of the class described comprising a member having a relatively wide range of primary adjustment. and clamping means therefor permitting a' limited range of movement of said member. r p r V I 8. Ina carburetor, an air valve a'spring resisting the opening of-sa-id' valve,.and means for varying the springpressure comprising a lever acting to compress said spring, an adjusting screw limiting the return movementof said lever and means engaged on said screw adapted to limit the range of movement thereof. 7

4.;In a 'carbureter, an air. valve a; spring resisting the opening of. said valve, and

.means for varying the springjpressureconiprising af lever acting to compress said spring, an ad usting screw" limiting the return movement of said lever, a notched 001-.

lar clamped to said screwand clicker means engaging the notches in said collar forindieating the degree of adjustment of said screw from normal.. V;

-5. In a; carbureter, an airvalve, 1'esisting".the opening of. said valve,.and' means for "varying the spring-pressure com-l prising a lever acting-to" compress said spring, an: adjusting screw limiting the 1 re a. spring Y 

